hello, I'm a 20 year old man. I've recently had a lot of strange pain in my knees. I used to run and weight train, but now I don't really do a lot of that. My knees have always cracked a lot, but recently they've been cracking more, and it's sort of a fizzled cracking. My main concern is that whenever I squat down, I feel this strange tightness, like I'm going to pull something. It happens more on my right knee and after I squat it makes a popping when I extend it forwards all the way. I also here this strange faint, fizzling sound when I bounce on my knees, I imagine it might be crepitus. My left knee also makes this strange shifting feeling when I fold it inward and flex. However, my knees aren't tight, they don't hurt regularly or after I run. Any guesses?